Ferroelectric Domain Structure of Lanthanum‐Modified Lead Titanate Ceramics

Abstract
The ferroelectric domain configurations in lanthanummodified lead titanate ceramics have been studied by transmission electron microscopy in conventional, analytical, and high‐resolution modes. Results indicate a preponderance of (101), twin‐related 90° domains of equilibrium width 50 to 100 nm. These values are consistent with those derived from consideration of elastic strain energy. Below a critical grain size of approximately 0.3 μm, single‐domain grains are found. A domain wall energy of 1 mJ/m2 was calculated based on this observation. Within such twins are occasionally found ordered domains, displaying little or no misorientation with respect to one another. In addition, (001), 180° domains were observed.